Sir John Herbert Lewis GBE PC (27 December 1858 – 10 November 1933) was a Welsh Liberal politician.
Born at Mostyn Quay, Flintshire, Lewis was one of five sons of Enoch Lewis and Elizabeth Roberts. It is possible that Lewis was related to C.S. Lewis. This speculation is the result of the fact that C.S. Lewis's grandfather, Richard Lewis, was born in Flintshire in 1775. He was educated at McGill University and Exeter College, Oxford.
Lewis was the first Chairman of Flintshire County Council. He was Member of Parliament MP for Flint Boroughs 1892-1906. In 1894, he resigned the Liberal Whip in the so-called 'Welsh Revolt', joining David Alfred Thomas, David Lloyd George and Frank Edwards. In a letter to T. E. Ellis, Lewis wrote to his friend, then Chief Whip: 'I will never again fight a constituency as an official Liberal.' Although he later recanted, this episode was illustrative of Herbert Lewis' moral seriousness. With Lloyd George, Lewis was an enthusiastic supporter of Cymru Fydd, a nationalist movement within Welsh Liberalism. Along with Lloyd George and David Alfred Thomas, he opposed the Boer War at the 1900 General Election. He was elected for Flintshire in 1906;
Lewis was a Lord of the Treasury, 1905–1908. He was re-elected twice in 1910, the second time unopposed;